Adds support for Map types in feign for `@RequestHeader` and `@RequestParam`.

Fixes gh-1360

* #1341-single-deferred-result:
  #1341 SingleDeferredResult should uses RESULT_NONE from DeferredResult instead of having its own empty result.

#1341 SingleDeferredResult should uses RESULT_NONE from DeferredResult instead of having its own empty result.

* pull1485:
  fix spell error

fix spell error

In addition to `eureka.instance.hostname` property you can now defined `sidecar.hostname` in order to set different hostname from application and its sidecar.
However if `eureka.instance.hostname` is present it will override `sidecar.hostname`.

Fixes #981

Set the default buffer size to 8192 to match Tomcat and Jetty defaults
Use a buffer per worker thread and use it for subsequent requests

Fixes gh-1546

fixes gh-1600

Pass along client config in RibbonCommand.run.  

Fixes gh-1530

Make FeignClientRegistrar implement EnvironmentAware to inject the environment.  

Fixes gh-1568

Fix potential decoding and reencoding issues in query params when using SimpleHostRoutingFilter (#1464)

Some webserver are picky with the encoding (uWSGI for example) and the current code behavior of decoding and reencoding the query string can lead to valid requests
rejected by the backend after the modifications in Zuul. This commit adds an optional parameter to force the original encoding of the query string in SimpleHostRoutingFilter.

Fixes gh-971

Fixes #1440

Update spring-cloud-netflix.adoc

 - Remove unintended white-space
 - Specify imagesdir

This will clear up empty 200 responses.

fixes gh-1123

s-c-commons creates an AutoServiceRegistrationProperties bean if enabled.

This commit only auto registers with eureka if that bean is available.

use `com.netflix.loadbalancer.DummyPing` instead of `NoopPing`

This eliminates the startup of another theadpool.

fixes gh-1504

Don’t add URL protocol when url is set using EL

Uses configuration from IConfigClient reference to always use the most up to date configuration.  Fixes #1481.

Document Eureka client zone config

Defaults were set too late and were overriding values set in the environment.

Specifically, spring.application.name took precedence over eureka.instance.appname.

 fixes gh-1516

Specifically, add `@ConditionalOnBean(EurekaClient.class)`.

Fixes an issue where eureka and ribbon are on the classpath, eureka.client.enabled=false which would cause a bean not found exception.

fixes gh-1511

(cherry picked from commit d1f8c031)

Upgrade Eureka to 1.6.1.  Fixes #1495.